1. Field of the Invention
The present invention generally relates to cooling air supply systems of small vehicles. More particularly, the present invention relates to brake system cooling arrangements for small vehicles, such as an all terrain vehicles, for example.
2. Description of the Related Art
Small all terrain vehicles generally feature a frame assembly that supports a fuel tank and a seat. An engine is generally positioned within an engine compartment defined by the frame assembly and is located generally beneath the seat and/or fuel tank. In conventional small all terrain vehicles, the frame assembly is supported by at least one front wheel and two rear wheels. The wheels are driven by a shaft, belt or chain drive configuration. Depending upon the drive configuration, the vehicle can be driven by two of the wheels or all of the wheels.
A braking system is employed to stop these vehicles. In some arrangements, such as that shown and described in U.S. Pat. No. 4,719,984, the vehicle is provided with a brake disc that is connected to a drive shaft, which is connected to the rear wheels. The brake disc is squeezed between a pair of brake pads that are operated by a brake caliper. The brake disc and the brake pads can be positioned within a housing to protect the brake components from damaging contact (e.g., see Japanese Patent Publication No. Hei 7-37819).
During braking, friction heat is generated by the brake system. In arrangements in which a rear drive shaft carries the brake disc, the engine often is positioned forward of the brake disc. Accordingly, the normal flow of air created over the brake system during vehicle operation generally is reduced or eliminated. Because heat has an adverse effect on brake performance, a cooling system for Such a brake system is desired.
While cooling air has been supplied to a shaft drive brake system in the past, such attempts to cool the brake system have created other problems. For instance, depending upon the construction of the cooling system, heat from the engine or the exhaust system can increase the temperature of the air being supplied to the brake system. If the air is heated in this manner, the cooling efficiency of the cooling system is adversely affected. In addition, depending upon the construction of the cooling system, ducting used in the cooling system can be prone to clogging during operation of the vehicle due to the offroad nature of such operation. If an operator does not regularly check the cooling system for clogging and clear the ducting if necessary, the cooling system will fail to operate properly.